Looking out our window daily certainly shows "weather," but it really doesn't tell us much, or anything, about "climate."

We need to go further afield and look at data collected over a period of time in order to get a view as to what is happening to Earth's climate. A case in point is the snow and ice cover around the globe and what that information tells us.

Last fall, the U.S. Geological Survey (USGS), one of the world's leading research organizations, issued a report: "Most Alaska Glaciers Retreating, Thinning and Stagnating." It says that more than 99 percent of Alaska's large glaciers are retreating, while a handful are advancing. The 550-page report will serve as a major reference point for glaciologists now and in the future.

One set of data, black-and-white photographs, was particularly poignant in documenting changes in a large number of glaciers over the past six or more decades. One of the authors found almost the exact spot today where a photo had been taken many decades earlier. When the old photograph is compared to the new one, the results are visually startling. In the new photographs, the glaciers have shrunk in height, width and length or even disappeared from sight entirely. In addition to photographs are satellite images, maps and other data documenting the distribution, status and behavior of these glaciers in Alaska.

Another report by the Earth Policy Institute in early 2008 took a global look at the status of glaciers. It reported on examples of ice melt around the world. Data here covered the Greenland Ice Sheet, Arctic Sea Ice, Antarctic Ice Sheets, glaciers in the Himalayas in Southeast Asia, the Pamirs in Central Asia, the Alps in Western Europe, the snowfields on Mount Kilimanjaro in Tanzania, Africa, the Andes in South America and the Southern Alps in New Zealand, to name just a few. In all these cases, there have been massive losses of ice cover and ice mass over the past several decades.

Something is going on. And it is global in nature.

Startling Results
Closer to home, in the Cascade Mountains of Washington state, things are also a changing. Dr. Mauri Pelto, as reported in the Press-Republican in the fall of 2008, is a professor of environmental sciences at Nichols College in Massachusetts who has been studying the glaciers there for the past 25 years.

In the 1980s, science budgets were being cut, and as a graduate student, Pelto was looking for financial support. The National Academy of Sciences (the top scientific body in the United States) had just identified climate change as an issue worthy of study and support. As a skier and a skeptic, he was looking to find a hole in this issue. The Academy of Sciences wanted someone to monitor the mountain glaciers across an entire mountain range, and he took on the project. Pelto sees this now as a 50-year project and only half over, but the results of his research so far are startling. The glaciers in the North Cascades are "dying." They are disappearing. One third of the glaciers "are doomed" to disappear. The remainder "may have a chance if the world begins to address the issue of climate change," according to Pelto.

He finds it hard to believe that anyone still questions that global warming is real.

And the data doesn't stop here. In 2007, almost a million square miles of Arctic Sea ice disappeared, beyond the long-term average since satellites began measurements in 1979. The increase in the extent of open water amounted in size to the expanse of California six times over. Scientists studying this were almost unnerved with this unprecedented melting and their inability to understand and to predict it. The pace of change far exceeded what had been estimated by almost all of the simulations used to see how the Arctic would respond to increasing greenhouse emissions. The reasons for this melt are still not clear, but studies continue.

Retreating Glaciers
One area of interest is the "feedback effect" of open water exposed to sunlight versus the same area with ice cover. Ice reflects about 90 percent of the sun's radiant energy back into space, whereas water absorbs about 90 percent of that same solar radiation. With more open water absorbing more radiation, more warming occurs, with more loss of ice cover. While ice loss in the Arctic in 2008 was not as extensive as in 2007, it still far exceeded the 1979-2005 average.

I have seen signs of glaciers melting in two widely separated areas in the Canadian Arctic. While hiking in 1988 on Baffin Island in Auyyuiituq National Park (Auyyuiituq is Inuit for "the land that never melts") on the Arctic Circle, we saw numerous mounds of gravel, rocks and boulders pushed up into terminal moraines. We could see the glacial tongues of ice responsible for bulldozing these features far up the mountainsides. At that time, we just noted that the glaciers had retreated, as we did not have the words "global warming" in our vocabulary.

I had a similar experience while hiking in the western Canadian Arctic in 1992, in Kluane National Park, Yukon. Photographs of the huge glacier there had fueled our footsteps and inner visions; we found it much diminished in size. It, too, had retreated far up the valley. These were experiences, not scientific studies, but telling in retrospect.

The climate is changing; the Earth is warming.

The scientific career of Raymond N. Johnson, Ph.D., spanned 30 years in research and development as an organic/analytical chemist; he is currently founder and director of the Institute of Climate Studies USA (www.ICSUSA.org). Climate Science is published the first Sunday of every month.